Bug 33910: Improve translation of title tags: Authorities

Bug 33910: Improve translation of title tags: Authorities

This patch updates authorities templates so that title
tags can be more easily translated.

To test, apply the patch and confirm that the following authorities
pages have the correct title tags:

- Authorities -> Authorities home page
  - Authority search results
    - Authority details
      - Edit authority
      - Merge authorities
- Cataloging -> New or edit record
  - Trigger the authority search plugin on a field which is linked to an
    authority type.

Signed-off-by: Sam Lau <samalau@gmail.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>